See e.g. [1]}, [2]}, [3]}. Moreover, by using the rough eigenfunction bound (REF ),
\(\sum _{\tau _\ell \in [1,2\lambda ]}\big |h(\tau _\ell )e_{\tau _\ell }(z) \overline{e_{\tau _\ell }(x)} \big |\lesssim \lambda ^n,\,\,\,\forall \, z,\,\,x\in M.\) 
